The present invention relates to antennae and, more specifically, to antennae with multi-frequency, multi-radiation angle, multi-polarization and multi-pattern communication capabilities.
Radio frequency (RF) antennae are used in a wide variety of fixed, portable and mobile communications implementations. In many cases, such antennae are limited as to their radiation angle, their frequency band or their polarization angle with corresponding resulting limits as to their communications coverage capabilities.
In general, an “omni-directional” antenna provides moderately-effective coverage to all stations in its coverage area while a bi-directional or unidirectional antenna provides coverage which favors one or two areas. Thus, in high frequency (HF) bands of 3-30 MHz, a lower antenna radiation angle from a ground or vehicle mounted antenna may favor distant stations while a higher antenna radiation angle might favor more local stations. By contrast, in very high frequency (VHF) and ultra-high frequency (UHF) bands of 30-300 MHz, a lower antenna radiation angle from a tower-mounted antenna may favor nearer stations while a higher radiation angle might favor more distant stations.